Predictive Factors of Amputation in Diabetic Foot

Background: Diabetic foot ulcers are a common complication of diabetes mellitus, often leading to progressive sensory deficits, impaired vascularization, and a predisposition to ulceration and gangrene. Untreated ulcers may cause recurrent infections that endanger a patient's life. Amputation of part of the limb up to a well-vascularized level is one of the treatments employed for untreated ulcers. Objectives: Laboratory data were analyzed with the aim of identifying risk factors related to surgical amputation treatment of diabetic foot. We believe it is useful to identify risk factors that can be altered from a reversible condition in the clinical decision-making of treatment, thus manifesting themselves in a timely manner to provide the patient with an alternative to surgical amputation of the lower limb. Methods: Our retrospective study was conducted by the Department of Orthopedics and Traumatology at the Fondazione Policlinico Universitario Agostino Gemelli IRCCS in Rome. We recruited 200 patients who underwent lower limb amputation for diabetic foot between 2017 and 2021 and had blood tests both 30 days and within 5 days before the first surgery. Results: This case-control study revealed a significant negative correlation between hemoglobin (Hb) levels and the occurrence of leg amputations. In contrast, C-reactive protein (CRP) levels, the neutrophil-to-lymphocyte ratio (NLR), and the platelet-to-lymphocyte ratio (PLR) showed significant positive correlations with leg amputations. A 3-year follow-up of the cases also revealed a significative positive correlation between age, white blood cells (WBC) count, NLR, PLR, and death at 3 years. Conclusions: Our findings suggested that lower Hb levels and elevated CRP, NLR, and PLR levels in patients with diabetic foot disease may be associated with a higher risk of lower-limb amputation. Unexpectedly, this study also demonstrated that elderly age, WBC, CRP, NLR and PLR levels may be associated with a negative prognosis for these patients. These findings highlighted the importance of monitoring these laboratory values in diabetic patients to identify individuals at higher risk of leg amputations and implement appropriate interventions to prevent or minimize the occurrence of this severe complication.